US 11,695,431 B2
LPWAN communication protocol design with turbo codes
Wenwen Tu, Santa Clara, CA (US); and Wensheng, Fremont, CA (US)
Assigned to STAR ALLY INTERNATIONAL LIMITED, Tortola (VG)
Filed by STAR ALLY INTERNATIONAL LIMITED, Tortola (VG)
Filed on Oct. 23, 2019, as Appl. No. 16/661,462.
Claims priority of provisional application 62/749,793, filed on Oct. 24, 2018.
Prior Publication US 2020/0136654 A1, Apr. 30, 2020
Int. Cl. H03M 13/25 (2006.01); H03M 13/29 (2006.01); H03M 13/09 (2006.01); H03M 13/00 (2006.01)
CPC H03M 13/258 (2013.01) [H03M 13/098 (2013.01); H03M 13/2963 (2013.01); H03M 13/617 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A method for decoding a message in an analog signal received at a receiver, the message being encoded in Turbo Codes and modulated for transmission as a plurality of analog values in the analog signal, the message being constructed according to an error detection scheme to allow determining from a Turbo Codes-decoded result whether or not the message has been successfully decoded under the error detection scheme, the method comprising:
(i) demodulating the analog signal to recover the Turbo Codes-encoded message;
(ii) iteratively decoding the Turbo Codes-encoded message for a predetermined number of iterations to obtain a current result, wherein the iterative decoding is performed in conjunction with evaluating a probability that the current result corresponds to a correctly received message, the probability relating to the deviation of the analog values in the analog signal received from their corresponding values at transmission, the probability being in substance:

OG Complex Work Unit Math
where (a) L is a length in number of bits of the Turbo Codes, (b) Xi and Yi are one of analog values at transmission and its corresponding analog value in the analog signal received, respectively, and (c) Xi is an analog value representing either a mean or a complement of Xi;
(iii) determining from the current result whether or not the message has been successfully decoded under the error detection scheme; and
(iv) returning to step (ii) for further iterative decoding of the Turbo Codes-encoded message when the message is determined not to have been successfully decoded under the error detection scheme.